Malicious PDF — malware analysis report

Static analysis result for SHA-256 88ab832c6eca0d48…

MALICIOUS

PDF

81.7 KB Created: 2021-08-21 23:58:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 1970add80499a39e666c25e506781cce SHA-1: 56156aa32ddc89153febe9049236cdfe00403a69 SHA-256: 88ab832c6eca0d4863b11b0864adaa9751bd548026f1b5d5106a3d9f77ce7e25
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a large number of links pointing to compromised CMS upload directories and disposable hosting, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly support its malicious nature. No scripts were extracted, but the embedded URLs are the primary indicators of compromise.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9076

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://aelma.com/sites/default/userfiles/file/82450459045.pdf In PDF document text
    • https://ercrs.org/wp-content/plugins/super-forms/uploads/php/files/fkeptmb8o7i8fi2do5l101hati/vimusobilixer.pdfIn PDF document text
    • https://nonbodepsg.com/uploads/files/kivadavewu.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1607bb5dd62109---sumurowenizeliximan.pdfIn PDF document text
    • https://nuevocoach.co.uk/wp-content/plugins/super-forms/uploads/php/files/b9584f56cfaa2929eb72367a48142546/wesatirupapuwapofup.pdfIn PDF document text
    • https://mudrun.com/home/mud/public_html/ckfinder/userfiles/files/kupukixokikedi.pdfIn PDF document text
    • http://tznjl.com/userfiles/files/newabozosafelevi.pdfIn PDF document text
    • https://realimpacto.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16087b84a87503---kiwijijefalos.pdfIn PDF document text
    • https://ecableapp.com/FCKeditor/FCKimgUpload/file/duvunolosetuvexovelafuzar.pdfIn PDF document text
    • https://christianboudreau.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c1e6ffd4c74---51246803886.pdfIn PDF document text
    • http://mrtowing.ca/Lawyers/userfiles/file/26254907855.pdfIn PDF document text
    • http://stalmost.pl/userfiles/file/xikemegowonuxadet.pdfIn PDF document text
    • http://aklond.com/UploadFilesfile///2021061114423954.pdfIn PDF document text
    • https://www.elementstraining.co.uk/wp-content/plugins/super-forms/uploads/php/files/j0m61u85gvh5oco4ui618d0ctv/93872444102.pdfIn PDF document text
    • http://tks-forever.com/upload/2021/07/28/file/34605673395.pdfIn PDF document text
    • http://ascensionchina.com/userfiles/file/1882869879.pdfIn PDF document text
    • https://webshopplus.nl/app/webroot/files/userfiles/files/mujiz.pdfIn PDF document text
    • http://ags-sib.ru/ckfinder/userfiles/files/65241600784.pdfIn PDF document text
    • http://varosom.hu/userfiles/files/wobofekojipugo.pdfIn PDF document text
    • https://grahampropertytax.com/wp-content/plugins/super-forms/uploads/php/files/4d544972893ad4c47c02c80865223fa9/pitudi.pdfIn PDF document text
    • http://mvdeastudio.it/userfiles/files/xarutavepezakik.pdfIn PDF document text
    • https://www.ibyservice.com/wp-content/plugins/super-forms/uploads/php/files/30350f8741d41a82fc33decbf3a2f763/96930066682.pdfIn PDF document text
    • https://gdr.co.il/wp-content/plugins/super-forms/uploads/php/files/ed92b135a010b0c273016f122a4dc1a7/jabebasazaki.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=fil%C3%B3sofo+her%C3%A1clito+de+efesoPDF link annotation
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ee74.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE74 10604 bytes
SHA-256: cd681c7a267074cca4f01df7ec8799ff43ff96865b5bcbb1738f29f7bb3eadbe
font_01_sfnt_off00010680.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10680 17568 bytes
SHA-256: 304c5c5f0eccb916bc525432757a67ee3d366cfd95e0b14e4cf5ac10dfcee45a
font_02_sfnt_off000132f8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x132F8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1